Japan’s growing plutonium stocks causing concern

Despite strong anti-nuclear power sentiment among Japanese caused by the 2011 nuclear disaster, the country will likely continue using atomic energy, meaning it must resolve the nagging issue of how to safely dispose of its nuclear waste

By Mari Yamaguchi / AP, ROKKASHO, Japan

Illustration: Yusha

How is an atomic-powered island nation riddled with fault lines supposed to handle its nuclear waste? Part of the answer was supposed to come from a windswept village along Japan’s northern coast called Rokkasho.

By hosting a high-tech facility that would convert spent fuel into a plutonium-uranium mix designed for the next generation of reactors, Rokkasho was supposed to provide fuel while minimizing nuclear waste storage problems. Those ambitions are falling apart as years of attempts to build a fast breeder reactor that would use the reprocessed fuel appear to be ending in failure. [A fast breeder reactor is a reactor which can generate more fissile material than it consumes.]

However, Japan still intends to reprocess spent fuel at Rokkasho. It sees few other options, even though the process will mean extracting plutonium that could be used to make nuclear weapons.

If the country were to close the reprocessing plant, about 3,000 tonnes of spent waste piling up there would have to go back to the nuclear plants that made it, and those already are running low on storage space. There is scant prospect for building a long-term nuclear waste disposal site in Japan. So work continues at Rokkasho, where the reprocessing unit remains in testing despite being more than 30 years in the making and the plant that would produce plutonium-uranium fuel remains under construction.

Foreign reporters were recently granted a rare and exclusive tour of the plant, where spent fuel rods lie submerged in water in a gigantic, dimly lit pool. The effort continues on the assumption that the 45 tonnes of plutonium Japan has produced so far will be used in reactors, even though that is not close to happening to a significant degree.

In nearby Oma, construction is set to resume on an advanced reactor that is not a fast breeder, but can use more plutonium than conventional reactors. Its construction, started in 2008 for planned operation the following year, has been suspended since the nuclear meltdowns at the Fukushima Dai-ichi nuclear power plant in March 2011 and could face further delays as Japan’s new nuclear watchdog prepares new safety guidelines.

If Japan decides that it cannot use the plutonium, it would be breaking international pledges aimed at preventing the spread of weapons-grade nuclear material. It already has enough plutonium to make hundreds of nuclear bombs — 10 tonnes of it at home and the rest in Britain and France, where Japan’s spent fuel was previously processed.

Countries such as the US and Britain have similar problems with nuclear waste storage, but Japan’s population density and seismic activity, combined with the 2011 disaster, make its situation more untenable in the eyes of the nation’s nuclear energy opponents. Some compare it to building an apartment without a toilet.

“Our nuclear policy was a fiction,” former Japanese minister of national policy Seiji Maehara told a parliamentary panel in November. “We have been aware of the two crucial problems. One is a fuel cycle: A fast-breeder is not ready. The other is the back-end [waste disposal] issue. They had never been resolved, but we pushed for the nuclear programs anyway.”

Nuclear power is likely to be part of Japan for some time to come, even though just two of its 50 functioning reactors are operating and it recently pledged to phase out nuclear power by the 2030s. That pledge was made by a government that was trounced in elections on Dec. 16 and the now-ruling Liberal Democratic Party was the force that brought atomic power to Japan to begin with.